Siphon for molten metals with suction actuator

ABSTRACT

A liquid transferring device, particularly for transferring molten aluminum from a first container at a higher elevation to a second container at a lower elevation, includes a siphon-shaped pipe having a U-shaped portion disposed within the liquid in the first container. The end of the U-shaped portion above the liquid level in the first container communicates with an elevated crucible element, and the bight of the U-shaped portion is formed with a bore communicating with the liquid in the first container for partially filling the device with the liquid to be transferred. The crucible element has a sealed upper end connected to a conduit and the conduit may be selectively connected to a source of gas under pressure or to a vacuum pump. Initially, the conduit is connected to the vacuum pump to draw the liquid into the crucible and siphon in order to prime the siphon and start a liquid transferring operation, which may be assisted by disconnecting the crucible from the vacuum pump and connecting it to the source of fluid under pressure to apply a pressure pulse to the liquid in the siphon-shaped pipe. Following priming of the siphon-shaped pipe, the liquid transfer operation continues automatically with the liquid in the first container flowing through the bore into the siphon-shaped pipe for discharge into the second container.

United States Patent [1 1 Colombani 1 Nov. 25, 1975 4] SIPHON FOR MOLTEN METALS WITH SUCTION ACTUATOR Piero Colombani, 6/1 Via Fiordalisi, Milan, Italy [22] Filed: Jan. 24, 1974 [21] Appl. No.: 436,335

[76] Inventor:

Solheim 164/133 UX Vogel et al. 222/204 X Primary ExaminerRobert B. Reeves Assistant Examiner-David A. Scherbel Attorney,- Agent, or Firm-McGlew and Tuttle ABSTRACT A liquid transferring device, particularly for transferring molten aluminum from a first container at a higher elevation to a second container at a lower elevation, includes a siphon-shaped pipe having a U- shaped portion disposed within the liquid in the first container. The end of the U-shaped portion above the liquid level in the first container communicates with an elevated crucible element, and the bight of the U- shaped portion is formed with abore communicating with the liquid in the first container for partially filling the device with the liquid to be transferred. The crucible element has a sealed upper end connected to a conduit and the conduit may be selectively connected to a source of gas under pressure or to a vacuum pump. Initially, the conduit is connected to the vacuum pump to draw the liquid into the crucible and siphon in order to prime the siphon and start a liquid transferring operation, which may be assisted by disconnecting the crucible from the vacuum pump and connecting it to the source of fluid under pressure to apply a pressure pulse to the liquid in the siphonshaped pipe. Following priming of the siphon-shaped pipe, the liquid transfer operation continues automatically with the liquid in the first container flowing through the bore into the siphon-shaped pipe for discharge into the second container.

11 Claims, 1 Drawing Figure SIPI-ION FOR MOLTEN METALS WITH SUCTION ACTUATOR BACKGROUND OF THE INVENTION This invention relates to a device for transferring from a first container liquid at a given elevation to a second container at a elevation lower than the liquid level within the first container.

More particularly, this invention relates to a device for transferring liquids having chemical and/or thermal features of such a nature as to prevent the use of valve means or the like, as in transferring molten metals, f.i. molden aluminium, from the smelting furnaces to the ladles and from the ladles to the holding furnaces or directly to the molds. The above aluminium transferring operation is usually carried-out by suitably oscillating furnaces and ladles. Alternatively, in order to avoid well known related drawbacks, the operation may be carried-out by means of particular pumping devices, that, however, require very frequent handlings and replacements of their movable components contacting the molten metal.

SUMMARY OF THE INVENTION An object of this invention is to provide a liquid transferring device that may operate under the preceding conditions and wherein no movable component of the device is in contact with the liquid, in order to avoid the previously referred drawbacks.

Another object of this invention is to provide a liquid transferring device of the type referred to and having a very simple and inexpensive structure.

According to this invention, the liquid transferring device comprises a siphon-shaped pipe that is hydraulically connected with a crucible element, while a bore is provided for partially filling the same upon immersion within the liquid to be transferred, the crucible element being connected with pneumatic means adapted to suitably subject the liquid within the crucible and siphon selectively to either a negative pressure or a positive pressure, in order to prime the latter and start the liquid transferring operation, which automatically continues through the bore feeding the siphon pipe. According to the invention, the pneumatic means may operate in order to impart a suitably controlled pressure pulse to the liquid partially filling the device. Alternatively or complementarily to the pressure pulse, the liquid may be sucked within the crucible by a suitable vacuum source, until attaining a predetermined head to allow or to make easier the following siphon priming operation.

In a preferred embodiment, the device comprises a siphon-shaped pipe having its outlet directed toward a second container wherein the liquid is to be transferred, and its inlet connected to a U-shaped pipe inserted into the liquid to be transferred from a first container. The U pipe has an opening or bore in its lower portion, while a gas-tight sealed crucible element is connected to the other end of the U pipe, above the liquid level in the first container.

In turn, the crucible is connected with pneumatic means adapted to subject the interior of the crucible to either a negative pressure or a positive pressure, to controllably draw the liquid upwardly into the crucible element and then to force the liquid through the U-siphon in order to prime the latter.

During the siphon priming operation, as carried out by means of a suitable pressure pulse, due to the position and shape of the bore in the U pipe, the liquid prevalently passes from the crucible to the siphon and does not return in into the first container.

In order to suitably carry out such a priming operation, it is necessary that, during the priming pneumatic pulse within the crucible element, the priming pneumatic fluid should not reach the said U pipe opening or bore. Accordingly, the siphon, U pipe and crucible should be suitably sized, in particular by providing a liquid volume inside the crucible substantially greater than that required for priming the siphon. Of course, the required pneumatic pulse must be suitably controlled too.

In order to interrupt the liquid transferring operation, through the medium of the pneumatic means, the crucible may be subjected to a positive pressure for a time sufficient to completely empty the latter and apply the pneumatic fluid or gas underpressure to the siphon pipe to break or interrupt the liquid stream in the latter. Another way to interrupt the liquid transferring operation, is to again subject the crucible to a negative pressure as by connecting it to the vacuum pump.

BRIEF DESCRIPTION OF THE DRAWING The single FIGURE of the drawing is a diagrammatic view with parts in section, showing a preferred embodiment of a device according to this invention.

DESCRIPTION OF A PREFERRED EMBODIMENT With reference to the accompanying drawing, a first container 1, f.i. in the form of an aluminium furnace or ladle, contains a liquid, e.g. molten aluminium, to be transferred to a second container 2, lying at an elevation lower than the liquid level 3 in the first container. In order to carry-out the transferring operation, a device according to this invention comprises a crucible 4 in the form of an essentially cylindrical shaped container having a lower end opening 5 and a top end opening, which is gas tightly closed by a cover 6. The device further comprises a siphon shaped pipe having a rising length 7, a top curve 8 and a descending length 9, the rising length 7 being connected, through a connecting U-shaped pipe 10, with the lower end of crucible 4, in order to allow the lower end opening 5 of crucible 4 to be hydraulically connected with siphon pipe 7, 8, 9. Further, connecting pipe 10 has a bore 11 hydraulically connecting the devicewith the liquid in first container 1, through a short pipe 12 having an axis perpendicular to the U pipe plane. Bore 11 and pipe 12 are suitably placed in the lower portion of U pipe 10 and preferably at the inner side of the U pipe bottom curve.

The shown device further comprises pneumatic means that are connected with crucible 4 through cover 6, by means of a suitable duct 14 that is fastened to crucible cover 6. The pneumatic means comprise, as diagrammatically shown, a suitable source 15 of a compressed fluid, f.i. compressed air, that feeds a pressure reducer 16 connected with duct 14 through an electrovalve 20. Between pressure reducer l6 and valve 20 a suitable pressure chamber 17 is provided.

In parallel with the above described pressure pulse circuit, a suction circuit is provided, the suction circuit having a vacuum pump 18 and an electrovalve l9. Finally the device comprises a further electrovalve 21 to connect duct 14 with the atmosphere, as well as a contact electrode 22, within the crucible 4, that is re- 3 sponsive to the liquid reaching a predetermined level within crucible 4.

In operation, the siphon rising length 7 and the U- shaped pipe 10 are immersed in the liquid within the first container 1. In their inoperative positions, the electrovalves l9 and of the pneumatic means are normally kept closed, while the electrovalve 21 is normally open, so that the crucible is in communication with the atmosphere through in duct 14 and the open electrovalve 21.

Accordingly, upon immersion of the device, the liquid in container 1 enters into U pipe 10 and siphon rising length 7 through bore 11, and reaches therein the same liquid level 3 as outside of the device in first container 1.

In order to carry out the liquid transferring operation, an operator, by means of a suitable electric pulse, simultaneously closes the valve 21 and opens the valve 19, so that the vacuum pump 18 causes the liquid to rise within crucible 4. When the liquid has reached the electrode 22 a further electric pulse simultaneously closes the valve 19, stops the pump 18 and opens the valve 20 in order to transmit a suitable air pressure pulse to the liquid within the crucible. Accordingly, the liquid flows into the U pipe 10 and rises within the siphon pipe 7, 8, 9 thus priming the same and transferring the liquid to second container 2, lying under the siphon pipe opening 13. The pressure pulse is then suitably disconnected by means of a timer (not shown) that closes the valve 20 just after the siphon pipe is primed.

Obviously, the sizes of the siphon pipe, the U pipe and the crucible, the pressure values and the pressure pulse time should be coordinated in order to obtain the siphon priming operation, with a liquid speed near the bore 11 sufficient to have mostly of the liquid previously stored into the crucible 4 to rise in the siphon.

The siphon pipe, when primed, continues the liquid transferring operation in a well known manner, by sucking the liquid through bore 11.

In order to interrupt the transferring operation, the electrovalve 20 may be further opened for a time sufficient to allow the compressed air to reach the siphon pipe. However, a different way for carrying out the interrupting step is to open again the valve 19. Further, means may be provided for transferring an exactly pre determined liquid volume by suitably timing the interrupting step.

The shown device may be then placed in its inoperative condition by closing the valves 20 and/or 19 and opening the valve 21 in order to put the device in condition for carrying-out a further transferring operation.

When handling molten aluminium, as in the shown preferred embodiment, the crucible 4, the U-shaped pipe 10 and/ or the siphon pipe 7, 8, 9 of the device may be made of suitable refractory material, cast iron or steel, and/or may comprise suitable warming means to avoid any liquid freezing therein, particularly in the portions thereof lying above the liquid level 3.

It is to be understood that, while this invention has been described in terms of a preferred embodiment thereof, many changes and modifications may be made therein without departing from the true spirit and scope of the invention.

1 claim:

1. A liquid transferring device for transferring high temperature liquids, contained at a given level in a first container, to a second container located at an elevation lower than such given level, said device comprising, in

combination, an inverted U-shaped liquid-transferring siphon pipe, having a rising length and a descending length extending from the bight of its inverted U-shape, positioned with its rising length in said first container and its descending length extending downwardly toward said second container with an outlet end at an elevation below such given level; said rising length communicating with the liquid level in said first container at a liquid inlet opening at a level below such given level; a gas-tightly sealed crucible vessel having a bottom inlet in fluid-tight communication with said rising length and communicating with said liquid inlet opening; and pneumatic pressure applying means communicating with said crucible vessel at its upper end and selectively operable to selectively apply either a negative or a positive pressure controllably to liquid in said siphon pipe to prime said siphon pipe for transfer of liquid from said first container to said second container.

2. A liquid transferring device, according to claim 1, in which said liquid inlet opening is constituted by a liquid inlet conduit communicating at one end with said liquid inlet opening and having its opposite end communicating with the interior of said first container for entry of liquid thereinto.

3. A liquid transferring device, according to claim 1, in which said liquid inlet opening is located within said first container beneath such given level at the lower portion of a pipe section connecting said bottom inlet of said crucible vessel with said rising rising length of said siphon pipe.

4. A liquid transferring device, according to claim 1, including duct means connecting said pneumatic pressure applying means to said crucible vessel; and valve means communicating with said duct means and selectively operable to connect said crucible vessel to atmosphere during a preliminary device filling operation.

5. A liquid transferring device, as claimed in claim 4, in which said pneumatic pressure applying means comprises a source of pneumatic fluid under pressure; and second valve meansselectively operable to connect said source of pneumatic fluid under pressure to said duct means for selectively and temporarily applying a positive pressure controllably to liquid in said siphon pipe.

6. A liquid transferring device, according to claim 5, in which said pneumatic pressure applying means further comprises a source of vacuum; third valve means selectively operable to connect said source of vacuum to said duct means for selectively applying a negative pressure controllably to liquid in said siphon pipe; and a liquid level detector positioned in said crucible vessel adjacent the upper end thereof and selectively operable, responsive to liquid in said crucible vessel attaining a predetermined level near to the upper end of said crucible vessel, to operate said third valve means to disconnect said source of vacuum from said duct means and to then operate said second valve means to connect said source of pneumatic fluid under pressure to said duct means to temporarily and controllably apply a positive pressure to liquid in said siphon pipe.

7. A liquid transferring device, according to claim 6, in which said crucible vessel is positioned above such given level; and a pipe containing the bottom inlet of said crucible vessel with said rising leg of said siphon pipe adjacent said liquid inlet opening, said pipe forming, with said rising length, a U-shaped pipe portion positioned in said first container.

8. A liquid transferring device, according to claim 4, in which said pneumatic pressure applying means comprises a source of vacuum; third valve means selectively operable to connect said source of vacuum with said duct means for selectively applying a negative pressure controllably to liquid in said siphon pipe; and a liquid level detector in said crucible vessel adjacent the upper end thereof and operable, responsive to liquid in said crucible vessel attaining a predetermined level therein near to the upper end of said crucible vessel, to operate said third valve means to disconnect said source of vacuum from said duct means and to control said pneumatic pressure applying means to selectively apply a positive pressure controllably to liquid in said siphon pipe.

9. A liquid transferring device, according to claim 1, in which said crucible is positioned above such given 6 level; and a pipe connecting said bottom inlet of said crucible vessel to said rising length of said siphon pipe adjacent said liquid inlet opening, said pipe forming, with said rising length, a U-shaped pipe portion positioned in said first container.

10. A liquid transferring device, according to claim 1, wherein said first container is a supply container for molten aluminum and said second container is a receiving container for the molten aluminum.

11. A liquid transferring device, according to claim 10, in which at least those portions of said device positioned above such given level are formed of a material having a melting point above that of molten aluminum; and warming means operatively associated with those portions of said device lying above such given level. 

1. A liquid transferring device for transferring high temperature liquids, contained at a given level in a first container, to a second container located at an elevation lower than such given level, said device comprising, in combinatioN, an inverted U-shaped liquid-transferring siphon pipe, having a rising length and a descending length extending from the bight of its inverted U-shape, positioned with its rising length in said first container and its descending length extending downwardly toward said second container with an outlet end at an elevation below such given level; said rising length communicating with the liquid level in said first container at a liquid inlet opening at a level below such given level; a gas-tightly sealed crucible vessel having a bottom inlet in fluid-tight communication with said rising length and communicating with said liquid inlet opening; and pneumatic pressure applying means communicating with said crucible vessel at its upper end and selectively operable to selectively apply either a negative or a positive pressure controllably to liquid in said siphon pipe to prime said siphon pipe for transfer of liquid from said first container to said second container.
 2. A liquid transferring device, according to claim 1, in which said liquid inlet opening is constituted by a liquid inlet conduit communicating at one end with said liquid inlet opening and having its opposite end communicating with the interior of said first container for entry of liquid thereinto.
 3. A liquid transferring device, according to claim 1, in which said liquid inlet opening is located within said first container beneath such given level at the lower portion of a pipe section connecting said bottom inlet of said crucible vessel with said rising rising length of said siphon pipe.
 4. A liquid transferring device, according to claim 1, including duct means connecting said pneumatic pressure applying means to said crucible vessel; and valve means communicating with said duct means and selectively operable to connect said crucible vessel to atmosphere during a preliminary device filling operation.
 5. A liquid transferring device, as claimed in claim 4, in which said pneumatic pressure applying means comprises a source of pneumatic fluid under pressure; and second valve means selectively operable to connect said source of pneumatic fluid under pressure to said duct means for selectively and temporarily applying a positive pressure controllably to liquid in said siphon pipe.
 6. A liquid transferring device, according to claim 5, in which said pneumatic pressure applying means further comprises a source of vacuum; third valve means selectively operable to connect said source of vacuum to said duct means for selectively applying a negative pressure controllably to liquid in said siphon pipe; and a liquid level detector positioned in said crucible vessel adjacent the upper end thereof and selectively operable, responsive to liquid in said crucible vessel attaining a predetermined level near to the upper end of said crucible vessel, to operate said third valve means to disconnect said source of vacuum from said duct means and to then operate said second valve means to connect said source of pneumatic fluid under pressure to said duct means to temporarily and controllably apply a positive pressure to liquid in said siphon pipe.
 7. A liquid transferring device, according to claim 6, in which said crucible vessel is positioned above such given level; and a pipe containing the bottom inlet of said crucible vessel with said rising leg of said siphon pipe adjacent said liquid inlet opening, said pipe forming, with said rising length, a U-shaped pipe portion positioned in said first container.
 8. A liquid transferring device, according to claim 4, in which said pneumatic pressure applying means comprises a source of vacuum; third valve means selectively operable to connect said source of vacuum with said duct means for selectively applying a negative pressure controllably to liquid in said siphon pipe; and a liquid level detector in said crucible vessel adjacent the upper end thereof and operable, responsive to liquid in said crucible vessel attaining a predetermined level therein near to tHe upper end of said crucible vessel, to operate said third valve means to disconnect said source of vacuum from said duct means and to control said pneumatic pressure applying means to selectively apply a positive pressure controllably to liquid in said siphon pipe.
 9. A liquid transferring device, according to claim 1, in which said crucible is positioned above such given level; and a pipe connecting said bottom inlet of said crucible vessel to said rising length of said siphon pipe adjacent said liquid inlet opening, said pipe forming, with said rising length, a U-shaped pipe portion positioned in said first container.
 10. A liquid transferring device, according to claim 1, wherein said first container is a supply container for molten aluminum and said second container is a receiving container for the molten aluminum.
 11. A liquid transferring device, according to claim 10, in which at least those portions of said device positioned above such given level are formed of a material having a melting point above that of molten aluminum; and warming means operatively associated with those portions of said device lying above such given level. 